Psystar said it plans to file a legal complaint against Apple alleging the computer vendor leverages an improper restraint of trade under the Sherman Antitrust Act and Clayton Antitrust Act by tying OS X to Apple hardware.

Psystar said it will request the court find Apple's End User Licensing Agreement (EULA) void and seek unspecified damages. And it plans to deny all charges made last month by Apple claiming violations of license, copyright and trademark.

Psystar Open Computer

Apple also accuses the open system vendor of pirating OS X and modifying its code to allow the operating system to run on Psystar machines. The company denies both charges. Psystar says it doesn't modify any proprietary code, claiming it uses open-source licensed resources for its OS magic.

"Every single copy of the OS is a purchased copy," said Rudy Pedraza, president and co-founder of Psystar. "Despite the allegations that there's a 'master disk,' that's not the case."

The company is still selling its Intel-based OpenComputer desktops running Leopard despite Apple's legal posturing. ®